Mayoral contender John Catsimatidis’ son, John Jr., 20, has been visiting Africa with Bill Clinton and daughter Chelsea. The former president and first daughter have spent a week traveling through the continent, working on projects for the Bill, Hillary & Chelsea Clinton Foundation. John Jr. joined the Clintons on visits to Malawi, Zambia, Tanzania, Rwanda and South Africa, where they campaigned for economic growth and better access to health care. Meanwhile, the senior Catsimatidis has been on the campaign trail, appearing Thursday at Desmond’s Steakhouse to celebrate his Resident magazine cover with Michelle-Marie Heinemann, Tony Lo Bianco and editor Christopher Pape.